1. Field of the Invention
The present invention relates in general to a sliding door stopper for limiting a sliding movement of a sliding door in its direction of opening in a damping or cushioning manner. Such a sliding door is employed for a cab-over type one box recreational or commercial vehicle, or other types of vehicle having a door opening in a side panel thereof, wherein the sliding door is adapted to be movable generally in parallel to the running direction along the vehicle side panel between its fully open and closed positions. More particularly, the present invention is concerned with such a sliding door stopper including a rubber block attached to a longitudinal end of a guide rail from which the sliding door is suspended.
2. Discussion of the Related Art
As one type of the sliding door employed for the recreational vehicle or commercial vehicle, there is known a sliding door having a construction in which rollers are attached to an upper portion of the sliding door, so that the rollers are supported and guided by a guide rail which is mounted on the vehicle body above the door opening, whereby the sliding door is suspended from the guide rail. In such a construction, a rubber buffer is generally attached to a longitudinal end of the guide rail, so that the roller or other part of the sliding door is brought into abutting contact with the rubber buffer when the sliding door has been moved to its fully open positioned. Thus, the sliding movement of the sliding door is limited, and its fully open position can be established in a cushioning or damping manner.
However, the above-described prior art arrangement in which the rubber buffer takes the form of an elastic body constituted simply by a solid rubber block, suffers from a drawback that the sliding door is likely to rebound or return from its fully open position towards its fully closed position due to a large restoring force generated by an elasticity of the elastic body, where the sliding door has been quickly moved to the fully open position, namely, where the sliding door is strongly brought into abutting contact with the rubber buffer. The guide rail has, in general, a protrusion in the form of a plate spring which is formed in the vicinity of its door opening end, so as to serve as a holding mechanism for holding the opened sliding door in the fully open position. That is, when the sliding door is moved towards the fully open position, the roller attached to the sliding door rolls over this protrusion just before the sliding door reaches the fully open position, so that the sliding door is held in the fully open position after the roller has passed the protrusion. However, the protrusion constituted by the plate spring has a difficulty in sufficiently preventing the sliding door from rebounding from the fully open position, particularly, where the sliding door is quickly opened.
Recently, there has been proposed an arrangement in which a locking mechanism is provided between the lower portion of the sliding door and the vehicle body, in an attempt to assuredly prevent the sliding door from being rebounding from the fully open position. According to the proposed arrangement, the sliding door is automatically locked in the fully open position, upon arrival of the sliding door at the fully open position. However, this arrangement also suffers from a drawback where the sliding door is quickly moved to be opened. That is, when the sliding door is strongly brought into abutting contact with the rubber buffer, the upper portion of the sliding door is forced back towards the fully closed position due to the elastic restoring force generated by the rubber buffer, whereby the entirety of the sliding door is shaked or rattled, accordingly making the vehicle operator or driver feel uneasy or even uncomfortable with the door opening operation. In the worst case, the sliding door is likely to interfere with the vehicle body due to a heavy shake of the sliding door, possibly resulting in some scratches or other damages on the vehicle body.